Frequent Questions

What is tritium and what are its health effects?

Tritium (H3) is a radioactive isotope of the element hydrogen (H) that emits ionizing radiation in the form of a weak beta particle. Tritium is produced naturally in the upper atmosphere and as a man-made byproduct from nuclear activities including weapons explosions or energy production. Tritium is commonly found in the environment in (tritiated) water because it readily reacts with oxygen to form tritiated water. People are exposed to small amounts of tritium since it is widely dispersed in the environment and the food chain. Tritium primarily enters the body when (tritiated) water is ingested, but may also enter through inhalation or absorption through the skin. Exposure to tritium increases the risk of cancer. However, tritium is considered one of the least dangerous radionuclides because it emits very weak radiation and passes through the body relatively quickly. This and additional information is available at EPA?s online tritium fact sheet: www.epa.gov/radiation/radionuclides/tritium.html